Efficacy and safety of apomorphine pump infusion in Filipino patients insufficiently controlled on oral anti-Parkinson medications: an open-label, pilot study

BACKGROUND

Apomorphine hydrochloride is used in the management of advanced Parkinson disease (PD), either as a rescue medication for off periods during levodopa therapy or as a maintenance pump medication. This is the first study to describe the effects of apomorphine in Filipino patients with PD.

OBJECTIVE

To evaluate the safety and efficacy of apomorphine ampules (APO-go®) pump infusion in the treatment of motor fluctuations in patients inadequately controlled on oral anti-Parkinson medications.

METHODS

Patients diagnosed with PD who developed motor fluctuations with levodopa were evaluated at baseline and at the end of the study using the Modified Hoehn and Yahr (H&Y) Scale, the Unified Parkinson's Disease Rating Scale (UPDRS) and the Abnormal Involuntary Movement Scale (AIMS). After initial assessment, patients were administered 20 ampules of apomorphine hydrochloride 10 mg/mL by infusion pump over 20 days. Intention-to-treat (ITT) analysis included all patients who completed at least one posttreatment assessment. Motor disability based on modified H&Y scores, motor function and complications of therapy pre- and posttreatment were compared using Wilcoxon Signed Rank test. Chi-squared test was used to compare outcomes by age and sex. Frequencies of adverse reactions were recorded to evaluate the tolerability of the medication.

RESULTS

Ten patients (mean age 63 ± 9.7 years), 3 male and 7 female, were enrolled in the study. Patients were given apomorphine for at most 16 days. The doses used were 2.5 mg/0.50 mL (n = 2), 3 mg/0.60 mL (n = 6), 4 mg/0.80 mL (n = 1) and 7 mg/1.40 mL (n = 1). After obtaining the threshold dose, two patients discontinued treatment. Eight of nine patients showed significant improvement in H&Y scores after treatment (p < 0.017). There was marked improvement after 10 days of treatment in at least five of 10 patients in terms of motor function using UPDRS, which included tremor (p < 0.034), rigidity (p < 0.002), facial expression (p < 0.014), finger taps (p < 0.008), foot taps (p < 0.014) and gait (p < 0.006). Significant changes from pre- to posttreatment scores in the frequency of dyskinesias (p < 0.010) and dystonia (p < 0.025) were observed. Nine focus areas of AIMS showed significant improvements in the muscles of facial expression (p < 0.020), upper (p < 0.016) and lower extremities (p < 0.010), incapacitation by abnormal movement (p < 0.010) and patients' awareness of abnormal movements (p < 0.039). Six patients experienced adverse events, none of which were related to the study drug.

CONCLUSION

Apomorphine hydrochloride pump infusion therapy is potentially effective and safe in the treatment of motor fluctuations in Filipino patients with PD. This pilot study springboards safe engagements of Filipino PD patients in multicenter, large-scale trials.

Cholecystokinin-Induced Duodenogastric Bile Reflux Increases the Severity of Indomethacin-Induced Gastric Antral Ulcers in Re-fed Mice

BACKGROUND/AIMS

We examined the involvement of cholecystokinin (CCK) in the exacerbation of indomethacin (IND)-induced gastric antral ulcers by gastroparesis caused by atropine or dopamine in mice.

METHODS

Male mice were fed for 2 h (re-feeding) following a 22-h fast. Indomethacin (IND; 10 mg/kg, s.c.) was administered after re-feeding; gastric lesions were examined 24 h after IND treatment. In another experiment, mice were fed for 2 h after a 22-h fast, after which the stomachs were removed 1.5 h after the end of the feeding period. Antral lesions, the amount of gastric contents, and the gastric luminal bile acids concentration were measured with or without the administration of the pro- and antimotility drugs CCK-octapeptide (CCK-8), atropine, dopamine, SR57227 (5-HT3 receptor agonist), apomorphine, lorglumide (CCK1 receptor antagonist), ondansetron, and haloperidol alone and in combination.

RESULTS

IND produced severe lesions only in the gastric antrum in re-fed mice. CCK-8, atropine, dopamine, SR57227 and apomorphine administered just after re-feeding increased bile reflux and worsened IND-induced antral lesions. These effects were significantly prevented by pretreatment with lorglumide. Although atropine and dopamine also increased the amount of gastric content, lorglumide had no effect on the delayed gastric emptying provoked by atropine and dopamine. Both ondansetron and haloperidol significantly inhibited the increase of bile reflux and the exacerbation of antral lesions induced by atropine and dopamine, respectively, but did not affect the effects of CCK-8.

CONCLUSIONS

These results suggest that CCK-CCK1 receptor signal increases bile reflux during gastroparesis induced by atropine and dopamine, exacerbating IND-induced antral ulcers.

Minimal adverse events occur when inducing emesis with apomorphine in brachycephalic, mesocephalic, and dolichocephalic dogs

OBJECTIVE

To determine risks of complications with emesis induction and whether facial conformation is associated with the frequency of complications.

ANIMALS

1,788 client-owned dogs that presented immediately or by referral from a primary care veterinarian following ingestion of toxic or foreign materials.

METHODS

Patients with emesis induced with apomorphine for removal of toxic or foreign materials were retrospectively identified. Collected data included patient factors, routes of apomorphine administration, other therapies, adverse events, and patient outcomes.

RESULTS

2 types of complications were identified in a very small number of patients (11 [0.6%]), with 3 (0.17%) having regurgitation postemesis and 8 (0.44%) having prolonged vomiting. No significant difference was found in the rates of repeated vomiting or regurgitation between brachycephalic dogs and nonbrachycephalic dogs (P = .375 and P = 1.00, respectively). Brachycephalic dogs had 1.6 times greater odds of having emesis induction due to toxin ingestion compared to foreign material ingestion. The presence of clinical signs of toxicity at the time of emesis induction was associated with regurgitation (P < .001), and the development of regurgitation was associated with admission to hospital (P = .001).

CLINICAL RELEVANCE

This study found no increased risk of complications when emesis was induced using apomorphine in brachycephalic breeds compared to nonbrachycephalic breeds, regardless of indication for emesis induction. Facial conformation is not a reason to withhold emesis induction.

D2 dopamine receptor-mediated mechanisms of dopaminergic system modulation in in vivo and in vitro experimental models of migraine

The dopaminergic system is implicated in the pathophysiology of migraine. However, the underlying mechanisms remain unclear. We explored the effects and mechanisms of dopaminergic system modulation in the in vivo and in vitro rat models of migraine. Dopaminergic agonist apomorphine, D2 receptor antagonists metoclopramide and haloperidol and 5-HT3 receptor antagonist ondansetron alone and together were tested in nitroglycerin-induced migraine model, in vivo. Likewise, the combinations of drugs were also tested on basal calcitonin gene-related peptide (CGRP) release in vitro hemiskull preparations. Mechanical allodynia was tested by von Frey filaments. CGRP concentrations in trigeminovascular structures and in vitro superfusates and c-Fos levels in the brainstem were determined by enzyme-linked immunosorbent assay. Meningeal mast cells were evaluated with toluidine blue staining. Apomorphine further enhanced nitroglycerin-induced mechanical allodynia, brainstem c-fos expression, trigeminal ganglion and brainstem CGRP concentrations and meningeal mast cell degranulation, in vivo. Haloperidol completely antagonised all apomorphine-induced effects and also alleviated changes induced by nitroglycerin without apomorphine. Metoclopramide and ondansetron partially attenuated apomorphine- or nitroglycerin-induced effects. A combination of haloperidol and ondansetron decreased basal CGRP release, in vitro, whereas the other administrations were ineffective. Apomorphine-mediated dopaminergic activation exacerbated nitroglycerin-stimulated nociceptive reactions by further enhancing c-fos expression, CGRP release and mast cell degranulation in strategical structures associated with migraine pain. Metoclopramide partially attenuated the effects of apomorphine, most likely because it is also a 5-HT3 receptor antagonist. Haloperidol with pure D2 receptor antagonism feature appears to be more effective than metoclopramide in reducing migraine-related parameters in dopaminergic activation- and/or NTG-induced migraine-like conditions.

Safety and tolerability of long-term apomorphine infusion in advanced Parkinson's disease: an Indian multi-center (APO-IND) experience

Advanced Parkinson's Disease (APD) is complicated by the emergence of motor and non-motor fluctuations, which are initially predictable and eventually become unpredictable, in part due to erratic gastric absorption and short half of oral levodopa. Attempts to manage such fluctuations with oral dopaminergic drugs often lead to disabling dyskinesias. Continuous Subcutaneous Apomorphine Infusion (CSAI), despite being approved for the treatment of APD since 1993, was approved in India only in 2019. We studied the safety, tolerability and efficacy of CSAI in Indian patients with APD in a registry design to raise local awareness of this important treatment. We conducted a prospective registry-based observational audit at 10 centers across different states of India. Patients with APD, not responding to or with significant side effects from oral dopaminergic therapy, were assessed at baseline and at month 6 and 12 following CSAI infusion. Fifty-one patients completed the study, CSAI significantly reduced the functional impact of dyskinesia (p < 0.01 at 6 months and p < 0.001 at 12 months). There was a significant improvement in the OFF-state from baseline (p < 0.01 at 6 months and p < 0.001 at 12 months) No discernible side effects were observed apart from mild site reaction (n = 7), nausea (n = 7) skin nodules (n = 2). CSAI demonstrated safety, efficacy, tolerability and improved quality of life in patients with APD, as shown in previous studies. Our study highlighted current existing inequalities in treatment availability, lack of awareness, knowledge gap, affordability and cost remains a concern regarding apomorphine use in Indian PD population.

Gastroparesis Worsens Indomethacin-Induced Gastric Antral Ulcers by Bile Reflux via Activation of 5-HT3 and Dopamine D2 Receptors in Mice

BACKGROUND/AIMS

We examined the contributions of gastric emptying and duodenogastric bile reflux in the formation of gastric antral ulcers induced by NSAIDs in mice.

METHODS

We used the murine re-fed indomethacin (IND) experimental ulcer model. Outcome measures included the appearance of gastric lesions 24 h after IND treatment and the assessment of gastric contents and the concentration of bile acids 1.5 h after re-feeding. The effects of atropine, dopamine, SR57227 (5-HT3 receptor agonist), apomorphine, ondansetron, haloperidol, and dietary taurocholate and cholestyramine were also examined.

RESULTS

IND (10 mg/kg, s.c.) induced severe lesions only in the gastric antrum in the re-fed model. The antral lesion index and the amount of food intake during the 2-h refeeding period were positively correlated. Atropine and dopamine delayed gastric emptying, increased bile reflux, and worsened IND-induced antral lesions. SR57227 and apomorphine worsened antral lesions with increased bile reflux. These effects were prevented by the anti-emetic drugs ondansetron and haloperidol, respectively. The anti-emetic drugs markedly decreased the severity of antral lesions and the increase of bile reflux induced by atropine or dopamine without affecting delayed gastric emptying. Antral lesions induced by IND were increased by dietary taurocholate but decreased by the addition of the bile acid sequestrant cholestyramine.

CONCLUSIONS

These results suggest that gastroparesis induced by atropine or dopamine worsens NSAID-induced gastric antral ulcers by increasing duodenogastric bile reflux via activation of 5-HT3 and dopamine D2 receptors.

Evaluation of subcutaneous versus intravenous administration of apomorphine for induction of emesis in dogs

OBJECTIVE

To prospectively compare the effectiveness and any adverse effects of apomorphine administered SC or IV for induction of emesis in dogs.

ANIMALS

42 client-owned dogs.

PROCEDURES

Dogs for which emesis induction was deemed appropriate by the attending clinician were prospectively randomized to receive apomorphine (0.03 mg/kg [0.01 mg/lb]) either SC (n = 20) or IV (22). Data collected included whether emesis was successfully induced, time from drug administration to emesis, number of emetic events, and adverse events (eg, sedation, protracted vomiting, or other).

RESULTS

Of the 20 dogs given apomorphine SC, 16 (80%) vomited. Of the 22 dogs given apomorphine IV, 18 (82%) vomited. With regard to route of administration, the number of dogs in which emesis was induced did not differ significantly. Median time to the first emetic event was 13.5 minutes (range, 3 to 32 minutes) in the SC treatment group and 2 minutes (range, 1 to 5 minutes) in the IV treatment group; the difference was significant. There was no significant difference in the number of emetic events or frequency of adverse events between the 2 groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Apomorphine administered SC or IV reliably induced emesis in dogs. Compared with SC administration of apomorphine, the time from drug administration to emesis associated with IV administration was significantly shorter, a finding that has clinical importance.

Apomorphine formulation may influence subcutaneous complications from continuous subcutaneous apomorphine infusion in Parkinson's disease

Continuous subcutaneous (s.c.) apomorphine infusion is an effective therapy for Parkinson’s disease (PD), but a limitation is the formation of troublesome s.c. nodules. Various chemically non-identical apomorphine formulations are available. Anecdotal experiences have suggested that shifting from one of these (Apo-Go PumpFill^®; apoGPF) to another (Apomorphine PharmSwed^®; apoPS) may influence the occurrence and severity of s.c. nodules. We, therefore, followed 15 people with advanced PD (median PD-duration, 15 years; median “off”-phase Hoehn and Yahr, IV) on apoGPF and with troublesome s.c. nodules who were switched to apoPS. Data were collected at baseline, at the time of switching, and at a median of 1, 2.5, and 7.3 months post-switch. Total nodule numbers (P < 0.001), size (P < 0.001), consistency (P < 0.001), skin changes (P = 0.058), and pain (P ≤ 0.032) improved over the observation period. PD severity and dyskinesias tended to improve and increase, respectively. Apomorphine doses were stable, but levodopa doses increased by 100 mg/day. Patient-reported apomorphine efficacy tended to increase and all participants remained on apoPS throughout the observation period; with the main patient-reported reason being improved nodules. These observations suggest that patients with s.c. nodules caused by apoGPF may benefit from switching to apoPS in terms of s.c. nodule occurrence and severity. Alternatively, observed benefits may have been due to the switch itself. As nodule formation is a limiting factor in apomorphine treatment, a controlled prospective study comparing local tolerance with different formulations is warranted.

Continuous subcutaneous apomorphine monotherapy in Parkinson's disease

INTRODUCTION AND OBJECTIVE

Continuous subcutaneous apomorphine (APO) treatment is one of the 3 therapeutic options for advanced Parkinson's disease (PD), in addition to deep brain stimulation (DBS) and intrajejunal levodopa. Data from previously performed studies show that few PD patients can achieve APO infusion as monotherapy. The current pilot study presents the authors' experience in achieving APO monotherapy.

MATERIAL AND METHODS

During the last 2 years, 9 patients with APO were treated in the Department of Neurology of the Medical University of Lublin; each patient was offered a 5-day duration APO treatment as monotherapy. The main indication for the APO therapy was advanced PD with motor fluctuations and the patient's non-agreement for DBS therapy. Mean age of treated patients - 65.11 years, mean disease duration - 7.67 years, mean Hoehn-Yahr - 2.67, mean L-dopa equivalent before APO treatment - 1751.11 mg, mean daily dose of apomorphine as monotherapy - 106.11 ± 14.09 mg.

RESULTS

All treated patients managed to achieve APO monotherapy. A statistically significant reduction was found in the duration of the 'off' states in the observed PD patients on APO monotherapy (p<0.05). No significant improvement was observed in the III motor score of the UPDRS on APO treatment, compared to optimized oral therapy used before APO treatment.

CONCLUSIONS

APO monotherapy can be achieved in advanced PD, and seems to be a good therapeutic option for this group of patients, especially in that it allows a significant reduction in the off-time which significantly simplifies the drug regime. Nevertheless, hospital admission with experienced neurologist supervision is recommended when establishing a PD patient's APO monotherapy.

[Prevention of medication errors in healthcare transition of patients treated with apomorphine]

The transition of patients between different levels of care process is a particular risk in the production of medication errors. The aim of this paper is to analyze the role of the pharmacist in preventing errors transition care to ensure a safe and cross pharmacotherapy of patients.Transversal, observational and descriptive study in a University Hospital that has a pharmacy service that integrates specialized inpatient care and health centers. Transition of care a patient treated with Apormorfina was analyzed to determine the keypoints of action of the pharmacist. Demographics, disease and medication history, and care transition episodes were collected through the pharmacy program and electronics history.The pharmacist did tasks adapting, reconciliation, management and reporting of medication to the health care team to prevent medication errors in care transition of patients treated with drugs requiring special handling .In conclusion, this work represents perfectly the key role of the pharmacist as coordinator of safe and transverse pharmacotherapy of patients.

[Treatment possibilities in advanced Parkinson's disease]

In the course of Parkinson's disease, advanced and late stages can be distinguished. In the advanced stage, levodopa has good effect on motor symptoms, but patient care is often hindered by levodopa-induced complications such as motor fluctuation and dyskinesias. In the late stage levodopa response becomes poor, falls, dementia and psychotic symptoms appear and patients often need hospitalization. In the advanced stage, the quality of life may be improved better by device-aided therapy than by best oral medical treatment. The alternatives are apomorhin pump, levodopa carbidopa intestinal gel with pump and deep brain stimulation. The therapy plan should be based on the principle: "the right treatment, to the right patient, at the right time".

Transplantation of melanocytes obtained from the skin ameliorates apomorphine-induced abnormal behavior in rodent hemi-parkinsonian models

Tyrosinase, which catalyzes both the hydroxylation of tyrosine and consequent oxidation of L-DOPA to form melanin in melanocytes, is also expressed in the brain, and oxidizes L-DOPA and dopamine. Replacement of dopamine synthesis by tyrosinase was reported in tyrosine hydroxylase null mice. To examine the potential benefits of autograft cell transplantation for patients with Parkinson’s disease, tyrosinase-producing cells including melanocytes, were transplanted into the striatum of hemi-parkinsonian model rats or mice lesioned with 6-hydroxydopamine. Marked improvement in apomorphine-induced rotation was noted at day 40 after intrastriatal melanoma cell transplantation. Transplantation of tyrosinase cDNA-transfected hepatoma cells, which constitutively produce L-DOPA, resulted in marked amelioration of the asymmetric apomorphine-induced rotation in hemi-parkinsonian mice and the effect was present up to 2 months. Moreover, parkinsonian mice transplanted with melanocytes from the back skin of black newborn mice, but not from albino mice, showed marked improvement in the apomorphine-induced rotation behavior up to 3 months after the transplantation. Dopamine-positive signals were seen around the surviving transplants in these experiments. Taken together with previous studies showing dopamine synthesis and metabolism by tyrosinase, these results highlight therapeutic potential of intrastriatal autograft cell transplantation of melanocytes in patients with Parkinson’s disease.

The role of endogenous neurotensin in psychostimulant-induced disruption of prepulse inhibition and locomotion

The neuropeptide neurotensin (NT) is closely associated with dopaminergic and glutamatergic systems in the rat brain. Central injection of NT into the nucleus accumbens (NAcc) or peripheral administration of NT receptor agonists, reduces many of the behavioral effects of psychostimulants. However, the role of endogenous NT in the behavioral effects of psychostimulants (e.g. DA agonists and NMDA receptor antagonists) remains unclear. Using a NTR antagonist, SR142948A, the current studies were designed to examine the role of endogenous NT in DA receptor agonist- and NMDA receptor antagonist-induced disruption of prepulse inhibition of the acoustic startle response (PPI), locomotor hyperactivity and brain-region specific c-fos mRNA expression. Adult male rats received a single i.p. injection of SR142948A or vehicle followed by D-amphetamine, apomorphine or dizocilpine challenge. SR142948A had no effect on baseline PPI, but dose-dependently attenuated d-amphetamine- and dizocilpine-induced PPI disruption and enhanced apomorphine-induced PPI disruption. SR142948A did not significantly affect either baseline locomotor activity or stimulant-induced hyperlocomotion. Systemic SR142948A administration prevented c-fos mRNA induction in mesolimbic terminal fields (prefrontal cortex, lateral septum, NAcc, ventral subiculum) induced by all three psychostimulants implicating the VTA as the site for NT modulation of stimulant-induced PPI disruption. Further characterization of the NT system may be valuable to find clinical useful compounds for schizophrenia and drug addiction.

[Candidate patient for treatment with continuous apomorphine infusion]

Subcutaneous apomorphine infusion has been shown to be effective in reducing motor fluctuations and, to a lesser extent, also the levodopa induced dyskinesias in patients with advanced Parkinson's disease (PD). Based on the literature data, the following article reviews the clinical features of PD patients in order to be considered candidates for this therapy. In general, the vast majority of patients with advanced PD can benefit from this therapy and the authors' experience suggests that it should be considered as soon as the conventional pharmacological therapy fails to significantly reduce the number of daily off hours.

[Subcutaneous continuous apomorphine infusion: treatment initiation and follow up]

Continuous apomorphine infusion has been an established treatment for advanced Parkinson's disease for over two decades. This article reviews the different methods for starting treatment and propose a consensus methodology for it, as well as for the modification of prior treatment, in order to standardize and reduce the variability of clinical practice.

[Treatment of apomorphine infusion adverse effects: subcutaneous nodules and neuropsychiatric complications]

Subcutaneous nodules and neuropsychiatric complications are the most relevant adverse effects during apomorphine infusion treatment. Subcutaneous nodules appear in almost all the patients and accurate information and training of both patient and caregiver is essential to minimise their impact on the treatment. Although neuropsychiatric complications are not more frequent than with other dopaminergic treatments, they are linked with increasing difficulty of treatment and worsening of patient's quality of life.

[Candidate patient for subcutaneous apomorphine injection]

Subcutaneous apomorphine injection is a fast-action, effective treatment option, that enables many patients to be rescued from predictable and non-predictable off episodes. It is an easy-to-use technique after minimum training. The neurologist can use it on patients with advanced Parkinson's disease only by following some basic procedures which are easily implemented in outpatient setting.

A water extract of Mucuna pruriens provides long-term amelioration of parkinsonism with reduced risk for dyskinesias

Dopaminergic anti-parkinsonian medications, such as levodopa (LD) cause drug-induced dyskinesias (DID) in majority of patients with Parkinson's disease (PD). Mucuna pruriens, a legume extensively used in Ayurveda to treat PD, is reputed to provide anti-parkinsonian benefits without inducing DID. We compared the behavioral effects of chronic parenteral administration of a water extract of M. pruriens seed powder (MPE) alone without any additives, MPE combined with the peripheral dopa-decarboxylase inhibitor (DDCI) benserazide (MPE+BZ), LD+BZ and LD alone without BZ in the hemiparkinsonian rat model of PD. A battery of behavioral tests assessed by blinded investigators served as outcome measures in these randomized trials. In experiment 1, animals that received LD+BZ or MPE+BZ at high (6mg/kg) and medium (4mg/kg) equivalent doses demonstrated significant alleviation of parkinsonism, but, developed severe dose-dependent DID. LD+BZ at low doses (2mg/kg) did not provide significant alleviation of parkinsonism. In contrast, MPE+BZ at an equivalent low dose significantly ameliorated parkinsonism. In experiment 2, MPE without any additives (12mg/kg and 20mg/kg LD equivalent dose) alleviated parkinsonism with significantly less DID compared to LD+BZ or MPE+BZ. In experiment 3, MPE without additives administered chronically provided long-term anti-parkinsonian benefits without causing DID. In experiment 4, MPE alone provided significantly more behavioral benefit when compared to the equivalent dose of synthetic LD alone without BZ. In experiment 5, MPE alone reduced the severity of DID in animals initially primed with LD+BZ. These findings suggest that M. pruriens contains water-soluble ingredients that either have an intrinsic DDCI-like activity or mitigate the need for an add-on DDCI to ameliorate parkinsonism. These unique long-term anti-parkinsonian effects of a parenterally administered water extract of M. pruriens seed powder may provide a platform for future drug discoveries and novel treatment strategies in PD.

Comparison of apomorphine and levodopa infusions in four patients with Parkinson's disease with symptom fluctuations

BACKGROUND

Motor fluctuations in patients with advanced Parkinson's disease may be successfully treated with subcutaneous apomorphine infusion or intraduodenal levodopa/carbidopa infusion. No comparative trials of these two alternatives were performed.

AIMS OF THE STUDY

We present a subanalysis from a randomized crossover clinical trial where levodopa infusion as monotherapy was compared with any other combination of pharmacotherapy in fluctuating patients. Four patients used apomorphine infusion and oral levodopa in the comparator arm. The results of these four patients are presented in detail.

METHODS

The duration of the trial was 3 + 3 weeks. Patients were video-recorded half-hourly on two non-consecutive days of both treatment arms. Blinded video ratings were used. Patient self-assessments of motor function and quality-of-life (QoL) parameters were captured using an electronic diary.

RESULTS

Ratings in moderate to severe "off" state ranged 0-44% on apomorphine infusion and 0-6% on levodopa infusion. Moderate to severe dyskinesias were not recorded in any of the treatments. QoL was reported to be improved in all patients on duodenal levodopa infusion.

CONCLUSIONS

Monotherapy with duodenal infusion of levodopa was more efficacious and brought greater QoL than combination therapy with apomorphine infusion in these fluctuating patients.

Apomorphine nodules in Parkinson's disease: best practice considerations

Apomorphine hydrochloride infusion therapy is used by approximately 1000 people with advanced Parkinson's disease in the UK (Britannia Pharmaceuticals Ltd, 2008). Subcutaneous nodules that develop as a result of these infusions can cause discomfort and may impact on the effectiveness of the drug therapy. Community nursing teams have a key role in supporting patients on apomorphine; they may be responsible for administering the drug, or supporting and empowering the patient or their carer to administer the infusion. A recent randomized controlled pilot study by a research group at the University of Hertfordshire investigated the use of therapeutic ultrasound for the treatment of apomorphine nodules. A number of observations about apomorphine nodules and the technique used to site infusions were made which may help to promote safe and effective management of apomorphine therapy. This article is a collaboration between one of the researchers and a Parkinson's disease nurse specialist from the University College of London Hospitals NHS Foundation Trust. It draws on best practice observations from both research and clinical experience and puts them in context of published research. It summarizes best practice considerations for administering infusions, identifies the current treatment and management options that participants from the trial reported using on their nodules, emphasizes the need for standardized documentation and suggests a rating system that may be useful to document nodule severity.

[Apomorphine and erectile dysfunction]

Erectile dysfunction is a common disease of andrology, for which current guidelines recommend oral agents as the first-line therapy. The dopamine agonist apomorphine acts on the central control of penile erection to allow a sublingual preparation to produce a prompt response. It is not contraindicated in patients on nitrate medication for coronary artery disease. The present review describes the pharmacodynamics, action mechanism, efficacy and adverse effects of apomorphine.

Apomorphine in the treatment of Parkinson's disease

Motor fluctuations, refractory to conventional medical management, are one of the most troubling aspects of Parkinson's disease. Apomorphine is a dopaminergic agent that has been known to the medical community for more than a century, but has only recently been developed to treat such motor fluctuations. In this article, the authors review the historical background, structure, mechanism of action, pharmacologic properties, clinical trials, indications and side effects, as well as avenues of further research, of apomorphine.

Subcutaneous apomorphine in patients with advanced Parkinson's disease: A dose-escalation study with randomized, double-blind, placebo-controlled crossover evaluation of a single dose

OBJECTIVE

To further explore the efficacy and safety of subcutaneous apomorphine (APO) in treating off episodes in APO-naïve patients with advanced Parkinson's disease (PD).

METHODS

56 patients receiving optimized oral anti-PD medication were evaluated on separate days for response to single increasing doses of APO. Acute response to oral anti-PD medication and APO dose escalation (2-10 mg) was evaluated under unblinded conditions. At the 4 mg APO dose, placebo was randomly introduced under double-blind crossover conditions.

RESULTS

Mean changes from pre-dose in Unified Parkinson's Disease Rating Scale motor scores indicated significant improvement following APO 4 mg versus placebo at 20 min (p=0.0002), 40 min (p<0.0001; maximum improvement) and 90 min (p=0.0229). Improvements showed significant dose-response at 20 min, 40 min (both p<0.0001) and 90 min (p=0.0049). Adverse events were more common with APO than placebo, and also showed significant dose-response (p<0.0001). Common adverse events associated with APO included yawning, dizziness, nausea, somnolence and dyskinesias, and were generally mild to moderate. There were no significant differences between APO and placebo in the incidence of hypotension associated with a postural change from a sitting to standing position.

CONCLUSIONS

Subcutaneous APO provided rapid, effective relief of off episodes associated with advanced PD.

Comparative trial of treatment satisfaction, efficacy and tolerability of sildenafil versus apomorphine in erectile dysfunction--an open, randomized cross-over study with flexible dosing

OBJECTIVE

Sildenafil and apomorphine are oral agents for the improvement of erection hardness. The aim of the study was a direct comparison of the two compounds under clinical routine conditions.

METHODS

131 previously untreated men with erectile dysfunction (ED) were enrolled in a cross-over trial and randomly allocated to 50 mg sildenafil or 2 mg apomorphine. Dose-adaptation was allowed as required.

RESULTS

Improvements in rigidity, the capacity to get and maintain an erection, and sexual confidence were statistically significantly larger with sildenafil (p <0.0001). 90% of the men were satisfied with sildenafil as compared to 46% with apomorphine. At study end, 95% of the patients preferred sildenafil. Both agents were well tolerated.

CONCLUSIONS

In this cross-over comparison under clinical routine conditions men reported superior efficacy of sildenafil vs apomorphine together with a statistically significantly higher treatment satisfaction.

Pharmacological characterization of psychosis-like behavior in the MPTP-lesioned nonhuman primate model of Parkinson's disease

Investigation of the pathophysiology of psychosis in Parkinson's disease (PD), as well as the assessment of potential novel therapeutics, has been limited by the lack of a well-validated animal model. MPTP-lesioned primates exhibit abnormal behaviors that are distinct from dyskinesia and parkinsonism and may represent behavioral correlates of neural processes related to psychosis in PD. Here we assess four types of behavior--agitation, hallucinatory-like responses to nonapparent stimuli, obsessive grooming, and stereotypies that are termed "psychosis-like"--and define their pharmacology using a psychosis-like behavior rating scale. By assessing the actions of drugs known to enhance or attenuate psychosis in PD patients, we find that the pharmacology of these behaviors recapitulates, in several respects, the pharmacology of psychosis in PD. Thus, levodopa and apomorphine elicited psychosis-like behaviors. Amantadine significantly decreased levodopa-induced dyskinesia but exacerbated psychosis-like behaviors. Haloperidol reduced psychosis-like behaviors but at the expense of increased parkinsonian disability while the atypical neuroleptics clozapine and quetiapine reduced psychosis-like behaviors without significant effect on parkinsonian disability. The response of different components of the psychotomimetic behavior suggested the involvement of both dopaminergic and nondopaminergic mechanisms in their expression.

[Prevention and treatment of fluctuations in patients with Parkinson's disease]

Fluctuations (wearing-off, on off phenomenon, dyskinesias) are a big challenge in the long term treatment of parkinsonian patients. We describe the current strategies for prevention and treatment of fluctuations. Special emphasis is put on two new methods which will soon be available. The new dopamine agonist Rotigotine (Neupro) can be transdermally applied. This is a rather simple way to achieve a continuous dopaminergic stimulation. The same goal is achieved by direct application of levodopa-/carbidopa-gelsuspension (Duodopa) in the duodenum by the help of an electronic pump.

Pharmacological MRI in awake rats reveals neural activity in area postrema and nucleus tractus solitarius: relevance as a potential biomarker for detecting drug-induced emesis

Drug-induced vomiting (emesis) is a major concern in patient care and a significant hurdle in the development of novel therapeutics. With respect to the latter, rodents, such as the rat and mouse, are typically used in efficacy and safety studies; however, drug-induced emesis cannot be readily observed in these species due to the lack of an emetic reflex. It is known that emesis can be triggered by neural activity in brain regions including area postrema (AP) and nucleus tractus solitarius (NTS). In this study, using pharmacological magnetic resonance imaging (phMRI) and a blood-pool contrast agent, we imaged the hemodynamic consequences of brain activity in awake rats initiated by the administration of compounds (apomorphine 0.1, 0.3 micromol/kg i.v. and ABT-594 0.03, 0.1, 0.3 micromol/kg i.v.) that elicit emesis in other species. Regional drug-induced relative cerebral blood volume (rCBV) changes and percent activated area within the AP and NTS were calculated, in which a dose-dependent relationship was evident for both apomorphine and ABT-594. Additionally, to correlate with behavioral readouts, it was found that the activation of AP and NTS was observed at plasma concentrations consistent with those that induced emesis in ferrets for both drugs. Our data thus suggest that phMRI in awake rats may be a useful tool for predicting emetic liability of CNS-acting drugs and may provide insights into depicting the underlying emetic neural pathways in vivo.

Behavioral effects of dopaminergic agonists in transgenic mice overexpressing human wildtype alpha-synuclein

Overexpression of alpha-synuclein causes familial Parkinson's disease and abnormal aggregates of the protein are present in sporadic cases of the disease. We have examined the behavioral effects of direct and indirect dopaminergic agonists in transgenic mice expressing human alpha-synuclein under the Thy-1 promoter (Thy1-aSyn, alpha-synuclein overexpressor), which exhibit progressive impairments in behavioral tests sensitive to nigrostriatal dopamine dysfunction. Male Thy1-aSyn and wild-type mice received vehicle, benserazide/L-DOPA (25 mg/kg, i.p.), high (2 mg/kg, s.c.) and low doses (0.125, 0.25, 0.5 mg/kg, s.c.) of apomorphine, and amphetamine (5 mg/kg, i.p.), beginning at 3 months of age, and were tested on the challenging beam, spontaneous activity, pole test, and gait. l-DOPA had a paradoxical effect and worsened the deficits in Thy1-aSyn mice compared with controls, whereas the high dose of apomorphine only produced few deficits above those already present in Thy1-aSyn. In contrast to wild-type mice, Thy1-aSyn mice did not show amphetamine-induced stereotypies. The results indicate that chronic overexpression of alpha-synuclein led to abnormal pharmacological responses in mice.

Slow oscillatory activity and levodopa-induced dyskinesias in Parkinson's disease

The pathophysiology of levodopa-induced dyskinesias (LID) in Parkinson's disease is not well understood. We have recorded local field potentials (LFP) from macroelectrodes implanted in the subthalamic nucleus (STN) of 14 patients with Parkinson's disease following surgical treatment with deep brain stimulation. Patients were studied in the 'Off' medication state and in the 'On' motor state after administration of levodopa-carbidopa (po) or apomorphine (sc) that elicited dyskinesias in 11 patients. The logarithm of the power spectrum of the LFP in selected frequency bands (4-10, 11-30 and 60-80 Hz) was compared between the 'Off' and 'On' medication states. A peak in the 11-30 Hz band was recorded in the 'Off' medication state and reduced by 45.2% (P < 0.001) in the 'On' state. The 'On' was also associated with an increment of 77. 6% (P < 0.001) in the 4-10 Hz band in all patients who showed dyskinesias and of 17.8% (P < 0.001) in the 60-80 Hz band in the majority of patients. When dyskinesias were only present in one limb (n = 2), the 4-10 Hz peak was only recorded in the contralateral STN. These findings suggest that the 4-10 Hz oscillation is associated with the expression of LID in Parkinson's disease.

Betamethasone does not prevent nausea and vomiting induced by the dopamine-agonist apomorphine

PURPOSE

The mechanism of the antiemetic actions of corticosteroids is not known. The purpose of this study was to evaluate if betamethasone can prevent nausea, vomiting or increase of vasopressin induced by apomorphine. Metoclopramide, a dopamine antagonist, was used as a control substance.

METHODS

Ten healthy volunteers were studied on three occasions. In a randomized order they were allocated to receive pretreatment with betamethasone 8 mg iv, metoclopramide 10 mg iv, and normal saline 2 mL as placebo on the three different occasions, 15 min before the administration of apomorphine 30 microg x kg(-1) s.c.. After administration of apomorphine, episodes of vomiting were recorded, and the intensity of nausea was estimated by the subject on a visual analogue scale (VAS 0-10 cm). Blood samples for analysis of plasma concentrations of vasopressin were analyzed.

RESULTS

One volunteer decided to withdraw, as he experienced akathisia after receiving metoclopramide. During the first two hours after apomorphine, eight of nine volunteers vomited both after betamethasone and placebo. One volunteer did not vomit after betamethasone and placebo but he experienced nausea. None of the volunteers vomited after metoclopramide (P < 0.01 vs betamethasone and placebo). The maximum VAS for nausea was significantly higher after betamethasone and placebo compared to metoclopramide (P < 0.01). The vasopressin levels increased after betamethasone and placebo, but there was no increase in any volunteer after pretreatment with metoclopramide.

CONCLUSION

This study demonstrates that betamethasone does not prevent nausea, vomiting and increase of vasopressin induced by apomorphine, whereas metoclopramide prevents apomorphine-induced emesis. Our work suggests that betamethasone does not have dopamine-antagonistic effects.

[Effects of subchronic introduction of phenamine and haloperidol on development of spontaneous catalepsy in mice]

The development of spontaneous and haloperidol-provoked catalepsy was investigated in more than 200 mice. It was found that spontaneous and haloperidolic catalepsies have the same mechanism of development. Injections of amphetamine followed by injections of haloperidol led to persistent changes of cateleptogenic behavior in mice. Less duration of spontaneous catalepsy may reflect functional condition of catecholaminergic brain systems similar to that of patients with psychotic disorder.

rTMS of supplementary motor area modulates therapy-induced dyskinesias in Parkinson disease

The neural mechanisms and circuitry involved in levodopa-induced dyskinesia are unclear. Using repetitive transcranial magnetic stimulation (rTMS) over the supplementary motor area (SMA) in a group of patients with advanced Parkinson disease, the authors investigated whether modulation of SMA excitability may result in a modification of a dyskinetic state induced by continuous apomorphine infusion. rTMS at 1 Hz was observed to markedly reduce drug-induced dyskinesias, whereas 5-Hz rTMS induced a slight but not significant increase.

Apomorphin bei der Behandlung des Morbus Parkinson

Apomorphine has long been used in many medical specialties. It is a highly potent D2-, D3- and D4-dopamine receptor agonist with a particularly high D1-dopamine receptor affinity. Due to its almost complete inactivation during liver passage it is usually applied subcutaneously. After rapid onset its effect is waning after about one hour. Apomorphine's action is not dependent on enteral dopamine resorption and on praesynaptic dopamine storage and dopamine secretion mechanisms. When applied subcutaneously its most common side effect is cutaneous nodules at the injection sites. Peripheral dopaminergic side effects, such as nausea and orthostatic hypotension, usually occur only during therapy initiation and respond well to domperidone. Hallucinations occur less frequently than with other dopamine receptor agonists. The apomorphine test determines the levodopasensitivity of a parkinsonian syndrome by application of an apomorphine bolus to distinguish between idiopathic Parkinson's disease and atypical parkinsonian syndromes. It indicates a levodopasensitivity in about 90% of the patients tested. False-negative results can occur in mild parkinsonian syndromes. A meta analysis indicates that intermittent subutaneous apomorphine applications (intermittent apomorphine therapy) with a self application device can reduce the daily duration of unpredictable off-phases by 48.8+/-8.7%. For this an average of 3.7+/-1.1 x 2.9+/-0.8 mg apomorphine has to be applied per day. Continuous subcutaneous apomorphine application with an extracorporal pump (continuous apomorhine therapy) during the wake phase reduces the duration of daily off-phases by 64.8+/-13.5% and the additional levodopa dose by 30.3+/-31.1%. 24-hour application reduces the daily duration of the off-phases by 63.5+/-19.1% and the additional levodopa dose by 65.5+/-21.9%. Levodopa-induced dyskinesias are also substantially reduced. A gradual conversion to an apomorphine monotherapy is possible. Even after prolonged treatment times no significant loss of efficacy occurs. With this profile apomorphine is a highly successful treatment option for off-phases and levodopa-induced dyskinesias in advanced cases of idiopathic Parkinson's disease which should be used before more invasive approaches are considered.

Transdermal iontophoretic delivery of apomorphine in patients improved by surfactant formulation pretreatment

The objective of the present study is to evaluate the efficacy and the safety of transdermal iontophoretic delivery of R-apomorphine, a potent dopamine agonist, in combination with surfactant pretreatment in patients with advanced Parkinson's disease. Iontophoresis patches were applied in 16 patients for 3.5 h, with 0.5 h of passive delivery followed by 3 h of current application at a current density of 250 microA/cm2. Eight of these patients were treated with a surfactant formulation prior to iontophoresis. The pharmacokinetics, pharmacodynamic effects, systemic and local side effects of R-apomorphine were assessed. The plasma concentration vs. time profiles upon iontophoresis of R-apomorphine were described successfully by a novel pharmacokinetic model. The model suggests that only 1.9% of the dose that has been released from the patch accumulated in the skin. The patients treated with the surfactant formulations showed a statistically significant increase of bioavailability (from 10.6+/-0.8% to 13.2+/-1.4%) and of the steady state input rate (from 75.3+/-6.6 to 98.3+/-12.1 nmol/cm2 h) compared to the control patients (iontophoresis without absorption enhancers). In five out of eight patients in the study group and in three out of eight patients in the control group, clinical improvement was observed.

Continuous dopaminergic stimulation reduces risk of motor complications in parkinsonian primates

Levodopa or short-acting dopamine (DA) agonist treatment of advanced parkinsonian patients exposes striatal DA receptors to non-physiologic intermittent stimulation that contributes to the development of dyskinesias and other motor complications. To determine whether continuous dopaminergic stimulation can delay or prevent onset of motor complications, four MPTP-lesioned, levodopa-naive cynomolgus monkeys were implanted subcutaneously with apomorphine containing ethylene vinyl acetate rods. Three other MPTP-lesioned monkeys received daily injections of apomorphine. Animals receiving apomorphine rods showed improved motor function ('ON' state) within 1 day of implantation, and remained continually 'ON' for the duration of treatment (up to 6 months) without developing dyskinesias. Injected animals also showed similar improvement in motor function after each apomorphine injection. However, these primates remained 'ON' for only 90 min and within 7-10 days all developed severe dyskinesias. Implanted monkeys evidenced local irritation, which was alleviated by steroid co-therapy.

The partial D2-like dopamine receptor agonist terguride acts as a functional antagonist in states of high and low dopaminergic tone: evidence from preweanling rats

RATIONALE

In adult rats, the partial D(2)-like agonist terguride acts as an antagonist at normosensitive D(2)-like post-synaptic receptors, while it acts as an agonist at the same receptors during states of low dopaminergic tone.

OBJECTIVE

The purpose of the present study was to determine whether partial D(2)-like agonists exhibit both antagonistic and agonistic actions during the preweanling period.

METHODS

In experiments 1 and 2 (examining the agonistic actions of terguride), preweanling rats were either given an escalating regimen of amphetamine to induce a state of amphetamine withdrawal or pretreated with the tyrosine hydroxylase inhibitor AMPT. Distance traveled was measured after rats were injected with saline, terguride (0.4-1.6 mg/kg), or the full D(2)-like receptor agonist NPA (0.01 mg/kg). In experiment 3 (examining the antagonistic actions of terguride), preweanling rats were pretreated with terguride 30 min before they were tested with saline, NPA (0.05 mg/kg), or amphetamine (1.5 mg/kg).

RESULTS

NPA had an exaggerated locomotor activating effect when tested under conditions of amphetamine withdrawal, while the partial D(2)-like agonist did not enhance distance traveled under any circumstance. Similarly, NPA increased and terguride did not affect the distance-traveled scores of AMPT-pretreated rats. In experiment 3, terguride pretreatment significantly reduced the distance traveled of amphetamine-treated and NPA-treated rats.

CONCLUSIONS

The behavioral evidence indicates that, during the preweanling period, terguride antagonizes D(2)-like post-synaptic receptors in a state of high dopaminergic tone; however, there is no evidence that terguride is capable of stimulating D(2)-like post-synaptic receptors during states of low dopaminergic tone.

A prospective evaluation of efficacy and compliance with a multistep treatment approach for erectile dysfunction in patients after non-nerve sparing radical prostatectomy

OBJECTIVE

To assess the response rate to different erectile aids in a consecutive series of patients treated with non-nerve sparing radical prostatectomy (NNSRP).

PATIENTS AND METHODS

Ninety-four potent men were counselled about the different treatment options to restore an assisted erection before they had NNSRP. They were invited to participate in a multiphase protocol involving the sequential use of different erectile aids which aimed at restoring erectile function after surgery. The first proposed treatment was oral apomorphine sublingual. Patients with a positive response to the 1-item overall efficacy question and a minimum score of 3 in both question 3 and 4 of the International Index of Erectile Function were considered responders to oral pharmacotherapy. Treatment with sildenafil was then suggested to those not responding. If patients did not respond to oral pharmacotherapy a trial with a vacuum erectile device was offered; those not responding to this were then offered intracavernosal injection therapy with prostaglandin-E alone as the first option, followed by a mixture of vasoactive agents if needed. In those in whom injections also failed, a penile implant was recommended. At the 1-year follow-up visit all patients were offered a second trial with oral therapy regardless of the treatment currently in use.

RESULTS

Seventy-six patients entered the protocol; there was no response to apomorphine. Five of 59 (8%) patients responded to sildenafil when they first used it at a mean of 7 months after NNSRP, while there were three additional responders in 22 patients who tried it for a second time a year later. Of patients achieving at least a complete tumescence sufficient for vaginal penetration, 52% and 60% were considered responders to the vacuum device and intracavernosal injections, respectively. Overall, 44% of patients enrolled in the protocol chose to use an erectile aid for at-home use. At the 1-year follow-up, only 20% of patients were still using an erectile aid, including two who had had a penile implant.

CONCLUSIONS

Up to 10% of patients may achieve a clinically significant erection with sildenafil after NNSRP, but 80% will not be using any erectile aid at 1 year after surgery. In the present study protocol the proposed erectile aids were largely inadequate for treating the permanent erectile dysfunction that follows NNSRP.

Apomorphine (Apokyn) for advanced Parkinson's Disease

Apomorphine (Apokyn) is now available for rescue treatment of "off" episodes in patients with advanced Parkinson's disease. It must be injected subcutaneously. Apomorphine in a variety of formulations has been used in Europe for many years. Like other dopamine agonists it can cause nausea and vomiting, orthostatic hypotension, drowsiness, "sleep attacks" and dyskinesias. It should be taken initially with an antiemetic to avoid nausea and vomiting.

A Comparative Review of the Options for Treatment of Erectile Dysfunction

The field of erectile dysfunction (ED) has been revolutionised over the last two decades. Several treatment options are available today, most of which are associated with high efficacy rates and favourable safety profiles. A MEDLINE search was undertaken in order to evaluate all currently available data on treatment modalities for ED. Phosphodiesterase type 5 (PDE5) inhibitors (sildenafil, tadalafil, vardenafil) are currently the first-choice of most physicians and patients for the treatment of ED. PDE5 inhibitors have differences in their pharmacological profiles, the most obvious being the long duration of action of tadalafil, but there are no data supporting superiority for any one of them in terms of efficacy or safety. Sublingual apomorphine has limited efficacy compared with the PDE5 inhibitors, and its use is limited to patients with mild ED. Treatment failures with oral drugs may be due to medication, clinician and patient issues. The physician needs to address all of these issues in order to identify true treatment failures. Patients who are truly unresponsive to oral drugs may be offered other treatment options.Intracavernous injections of alprostadil alone, or in combination with other vasoactive agents (papaverine and phentolamine), remain an excellent treatment option, with proven efficacy and safety over time. Topical pharmacotherapy is appealing in nature, but currently available formulations have limited efficacy. Vacuum constriction devices may be offered mainly to elderly patients with occasional intercourse attempts, as younger patients show limited preference because of the unnatural erection that is associated with this treatment modality. Penile prostheses are generally the last treatment option offered, because of invasiveness, cost and non-reversibility; however, they are associated with high satisfaction rates in properly selected patients. All treatment options are associated with particular strengths and weaknesses. A patient-centred approach based on patient needs and expectations is necessary for the management of ED. The clinician must educate the patient and provide a supportive environment for shared decision making. The management strategy must be supplemented by careful follow-up in order to identify changes in patient health and relationship/emotional status that may necessitate treatment optimisation.

Safety of entacapone and apomorphine coadministration in levodopa-treated Parkinson's disease patients: pharmacokinetic and pharmacodynamic results of a multicenter, double-blind, placebo-controlled, cross-over study

We investigated whether administration of the catechol-O-methyl transferase (COMT) inhibitor entacapone, at doses of 200 mg and 400 mg, alters the pharmacokinetics of apomorphine in Parkinson's disease patients experiencing severe motor fluctuations. In addition, the pharmacodynamics and safety of entacapone and apomorphine coadministration in these patients were examined. The study followed a three-sequence, three-period, crossover design. Patients were randomly assigned to one of three sequences that included single oral doses of entacapone 200 mg, entacapone 400 mg, and placebo in a predefined order. On 3 separate test days, study treatment was administered before apomorphine. The study evaluations (pharmacokinetics, tapping test, and dyskinesia evaluation [Abnormal Involuntary Movements Scale - AIMS]) were performed on these days. Furthermore, Unified Parkinson Disease Rating Scale (UPDRS) scores were evaluated at baseline and study end. Pharmacokinetic parameters for apomorphine (C(max), AUC, t(max), t(1/2)) were unchanged by the administration of entacapone, and changes in both the tapping test and AIMS score were similar with all treatments (entacapone 200 mg, entacapone 400 mg, and placebo). There was no significant difference in mean total UPDRS scores between baseline and study end. The administration of entacapone did not change the pharmacokinetic or pharmacodynamic effects of apomorphine in these patients or prolong the clinical effect of apomorphine. Thus, apomorphine may be safely administered to patients receiving therapy with levodopa and entacapone, providing a useful addition to treatment for patients with advanced Parkinson's disease.

Clinical efficacy of Apomorphine SL in erectile dysfunction of diabetic men

Although subgroup analyses from large randomised premarketing studies have shown that Apomorphine SL enhances the percentage of erections firm enough for sexual intercourse in diabetic men, the clinical role of the drug in this patient population remains to be elucidated. The aim of the present study was to assess the efficacy of Apomorphine SL in diabetic males with erectile dysfunction (ED) and to identify factors predicting those who may benefit from the treatment. A total of 130 diabetic patients were randomised to receive either four tablets of 3 mg Apomorphine or a matching placebo. Assessments of efficacy comprised the erectile function (EF) domain of the International Index of Erectile Function (IIEF) and the one-item global efficacy question (GEQ). Patients with both a positive response to the GEQ and an improvement of at least 5 points in the EF domain of the IIEF were considered responders and subanalysed by several parameters indicative of the severity of both ED and diabetes. Response rate was 17% after placebo and 22% after Apomorphine SL. The EF domain of the IIEF and both questions 3 and 4 scores did not significantly improve in either of the two arms over the baseline. A younger age and a lower Hb1Ac were significantly linked to the status of responder in the Apomorphine arm. Apomorphine SL failed to show a statistically significant benefit over a placebo, but 22% of patients had a clinically significant erectile response. These figures seem to suggest that the drug has a limited use for ED diabetic patients.